Pathophysiology
The individual components of atopy are all caused at least in part by allergy (type I hypersensitivity reactions). Therefore, atopic responses appear after the body is exposed to various allergens, for example pollen, dander, dust mites, certain foods, or chemical/physical irritants.
Although atopy has various definitions, in general, it is defined by the presence of elevated levels of total and allergen-specific IgE in the serum, leading to positive skin-prick tests to common allergens.
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